The possibility of a strike by Screen Actors Guild (SAG) against producers of made-for-cable TV shows loomed large Monday as the Alliance of Motion Picture & Television Producers (AMPTP) stepped in to aid cable producers after SAG asked members for strike authorization. The AMPTP said that it had offered SAG a 14-percent increase in residual payments, an amount that was in line with that recently negotiated with the Directors Guild of America and the Writers Guild of America. SAG observed that the 14-percent raise amounted to less than $5.00 per run for a day performer.